This helps me a lot to understand the foundation of quantitative genetics, especially now we're in a remote learning setting in the university. This is a great supplemental material! Thank you, Sir Thomas!
I love this! Thanks! What about the parent offspring regression though? When you argue that the farmers focus on additive variance because its more predictable it doesn't explain why the regression approach works.
We should stick to the well recognised established terminology. In Biology and genetics a complex trait is controlled by many genes. It is polygenic. If it’s controlled / influenced by other factors like the environment, then it is a multifactorial trait. Don’t use the term complex trait to mean anything other than polygenic trait otherwise we’re going to have confusion.
It’s not that only additive genetic variance is heritable, but instead that AGV is the most useful for hereditary studies and breeding. With additive genes, each allele contributes to the phenotype additively and equally. So AA has twice as much phenotype as Aa, and aa lacks the trait. For this reason, a breeder can always deduce the genotype by looking at the phenotype. This makes additive genes the most useful for breeding - no ambiguity. But to your point, all of the variances are genetically based and therefore all are inheritable.
Hello Sir, I am Yohannes form Ethiopia, I need your help on how to calculate heritability and genetic advance for Augmented design, because only checks are repeated in the experiments. I used Proc mixed model in SAS, in the 1st run, treat as fixed and block as random.while in the 2nd run treat partitioned to test genotypes (as random) and checks (fixed) to produce BLUP. Please, sir, I need your kind guidance to estimate heritability and genetic advance to complete my experiment (it is single trial, 225 testing genotypes,with 5 check and 5 block). I hope your response is soon!
@@thomasmennella5501 If you are ever looking for a real world example of this being used in a haplo-diploid breeding programme, take a look at www.beebreed.eu
@@thomasmennella5501 I appreciate your efforts in producing all of this material. Believe it, or not, I enjoyed your lectures so much that I went out and bought the book so I could follow along! :-D
@@thomasmennella5501 I enjoyed your lectures very much. Your knowledge and enthusiasm are so infectious that it's difficult not to be interested! I'm not alone either. I see so many comments extolling your ability to convey the subject in both a simple and rational manner. Thanks again!
well if you breed and A is big and a is small but all your cows are Aa they look like they are AA but arent so when the next generation comes around they are confused when some aa pop out. Sorry for broken English not first language
I see people are grateful for this video. I suppose thats good. I found it annoying with the ads and the crappy graphics. But maybe if I gave it a chance and actually listened to it, i would have found it worthwhile. Who knows.
